This proposal is an extension of a prospective longitudinal study of 111 cross-situationally (pervasive) and 50 situationally hyperactive children who were evaluated at two time points: childhood (ages 5-12 years) and late adolescence (ages 16-24 years). The adult outcome (ages 25-28 years) of these subjects will be compared to 51 siblings of pervasive probands and 78 non-hyperactive controls who were evaluated in adolescence, and who will be assessed as part of the present proposal. Only one prospective study of the adult status of childhood hyperactivity has been reported. However, its sample of 21-33 year olds (mean-25 years) suffered from high attrition (40%). The proposed study will provide a wealth of information as well as a powerful means for furthering our understanding of this common childhood disorder. First, the pervasive, sibling, and control groups represent replication samples which will be compared to our ongoing prospective study of 115 pervasive probands, 100 normal controls, and 40 siblings of probands who are currently being evaluated as adults. Both pervasive proband groups were seen at the same childhood clinic (directed by the PI), systematically selected by the same criteria, and will be assessed by the same instruments at follow-up. Second, a low attrition is anticipated, judging from our high retrieval rate on a similar sample, and since our core staff has remained intact for hover 10 years. Third, this is the only study to prospectively follow situationally hyperactive children into adulthood. Fourth, the combined samples of 226 pervasive probands (evaluated at three time points) will allow us to study associations that no other investigator can, because of inadequate base rates of behaviors and syndromes. The following outcome variables are targeted for study: psychiatric status (assessed by trained clinicians and structured interviews); social adjustment (assessed by the Weissman Social Adjustment Scale); self-ratings of symptoms (SCL-90-R); intellectual functioning (WAIS-R, WRAT-R) academic skills (school records); criminal history (official arrest records); and stature (height measurements). This study will provide the opportunity to investigate how childhood and adolescent behavioral, cognitive, and neuropsychological characteristics contribute to adult status in the largest prospective sample of an entire cohort of hyperactive children objectively evaluated at three time points.